WASHINGTON (AP) -- The Democratic presidential race between Hillary Rodham Clinton and Barack Obama has not only coaxed far more people to vote than in the past, it's also changed the mix of those showing up. Democratic voters are typically younger, likelier to be female and more racially diverse this year than they were in 2004, according to exit polls of voters from both campaigns. The historic matchup features Clinton vying to become the first female president, Obama the first black. Part of the difference could be because some 2004 primaries were held after Sen. John Kerry, D-Mass., had already clinched his party's nomination, reducing the incentive for many voters to participate. This year's race is still raging, though Obama has emerged as the front-runner. Some of the difference could also reflect changes in the country's population. Here are some ways the composition of Democrats voting has changed. Data from combined exit polls from 15 states that have held competitive Democratic primaries this year are compared with data from those same states four years ago. RACE: In 2004, 70 percent of Democratic voters in these states were white, 17 percent black and 8 percent Hispanic. This year 63 percent have been white, 19 percent black and 13 percent Hispanic. Clinton has led in contests so far among whites, chiefly white women, but has faded in recent primaries. She has won strong support from Hispanics, while Obama has had huge margins among blacks. SEX: Fifty-eight percent of this year's Democratic voters have been women, 4 percentage points more than in 2004. Clinton has a modest lead nationally among women, while Obama has a solid advantage with men. In the most noticeable changes, white men have dropped from 33 percent of 2004's Democratic voters to 27 percent this year. Minority women, meanwhile, have grown from 17 percent of voters to 21 percent now. AGE: Fifteen percent of this year's Democratic voters have been under age 30, compared with 10 percent in 2004. Obama has controlled this group. Those age 65 and up -- dominated by Clinton -- have dropped from 22 percent in 2004 to 18 percent this year. IDEOLOGY: This year's Democratic voters are slightly more liberal than four years ago. Fifty percent call themselves liberal -- including 19 percent saying they are very liberal, a group Obama leads. That's 3 points higher in both categories than in 2004. There's been a similar reduction in the proportion of Democrats calling themselves conservative. The data is from exit polls in the same 15 states in 2004 and 2008: Arizona, California, Connecticut, Delaware, Georgia, Louisiana, Maryland, Massachusetts, Missouri, New York, Oklahoma, South Carolina, Tennessee, Virginia and Wisconsin. It involved interviews with 23,773 Democratic voters in 2004 and 16,831 in 2008. The margin of sampling error for both was plus or minus 1 percentage point. The margin of sampling error for subgroups was larger.